CONTINUITY. 223 



with the other forms, and what a small proportion they 

 supply ; compare the shell-fish and amphibia of Palaeontology 

 with the other forms, and what an overwhelming majority 

 they yield ! 



There is nothing, as Professor Huxley has remarked, like 

 an extinct order of birds or mammals, only a few isolated 

 instances. It may be said the ancient world possessed a 

 larger proportion of fish and amphibia, and was more suited 

 to their existence. I see no reason for believing this, at least 

 to anything like the extent contended for ; the fauna and 

 flora now in course of being preserved for future ages would 

 give the same idea to our successors. 



Crowded as Europe is with cattle, birds, insects, &c., 

 how few are geologically preserved ! while the muddy or 

 sandy margins of the ocean, the estuaries, and deltas are 

 yearly accumulating numerous Crustacea and mollusca, with 

 some fishes and reptiles, for the study of future palaeonto- 

 logists. 



If this position be right, then, notwithstanding the immense 

 number of preserved fossils, there must have lived an im- 

 measurably larger number of organic beings which are not pre- 

 served, so that the chance of filling up the missing links, except 

 in occasional instances, is very slight. Yet, where circumstances 

 have remained suitable for their preservation, many closely 

 connected species are preserved in other words, while the 

 intermediate types in certain cases are lost, in others they 

 exist. The opponents of continuity lay all stress on the lost 

 and none on the existing links. 



But there is another difficulty in the way of tracing a 

 given organism to its parent forms, which, from our con- 

 ventional mode of deducing genealogies, is never looked upon 

 in its proper light. 



Where are we to look for the remote ancestor of a given 

 form ? Each of us, supposing none of our progenitors to 

 have intermarried with relatives, would have had at or about 

 the period of the Norman Conquest upwards of a hundred 

 million direct ancestors of that generation, and if we add the 

 intermediate ancestors, double that number. As each in- 

 dividual has a male and female parent, we have only to 



